9 results about "Rabi frequency" patented technology

Systems and methods are disclosed for determining interaction parameters for multiple particles, each particle having a ground state, an excited state, and one or more intermediate states The multiple particles are configured to interact with a plurality of electromagnetic fields associated with a (different) transition between two states. The method comprises performing a spectroscopy measurement, measuring an effective Rabi frequency Ωeff, measuring a single-photon Ramsey frequency ΩR i , and determining the interaction parameters based on the measured effective detuning δ eff, the measured effective Rabi frequency Ωeff, and the measured single-photon Ramsey frequencies ΩR i . The interaction parameters may be determined for each of the multiple particles. The interaction parameters may comprise a single-photon Rabi frequency Ω i for each electromagnetic field, which may be used to align the electromagnetic fields with respect to the particles.

This invention discloses an automatic calibration method for logic gates based on a neutral atom quantum computing system, and also discloses an automatic calibration method for logic gate fidelity based on a neutral atom quantum computing system. The method performs self-calibration on the fidelity of a two-qubit gate, including 420nm laser pointing self-calibration, 1013nm laser pointing self-calibration, Rydberg excitation Rabi frequency self-calibration, and single-photon Rabi frequency self-calibration; then it performs self-calibration on the ORMD waveform and ORMD phase; and finally, it performs self-calibration on the fidelity of an addressing single-qubit gate, including 795nm Raman light pointing self-calibration and single-qubit gate Rabi frequency self-calibration. This invention performs parameter self-calibration at fixed intervals to ensure that the logic gate fidelity remains at a high level. Without involving the installation of additional high-resolution laser position detectors, it uses a fully automated process to calibrate the fidelity of quantum logic gates, saving space in the physical system and the manpower costs required for calibration.

This invention discloses a method, system, device, and storage medium for suppressing energy level leakage, relating to the field of quantum information processing. The method applies parametric modulation to qubits to establish and activate effective exchange coupling between qubits under dispersive coupling conditions, thereby performing a two-qubit entanglement gate operation. During the gate operation, a computational subspace control model and an energy level leakage model are constructed by performing representational and unitary transformations on the system's Hamiltonian. Based on these models, the entanglement gate control pulse is optimized. The energy level correction introduced by the parametric driving is dynamically compensated through modulation of the effective Rabi frequency of time-shaping and time-dependent detuning parameters, thus suppressing energy level leakage from the computational subspace to higher energy levels. Compared with existing technologies, this invention improves the controllability and fidelity of entanglement gate operations under complex energy level structures and is applicable to quantum operations in modular quantum systems.

The invention discloses a method and system for realizing adjustable quantum simulation in ionic crystals, and the method comprises the steps: S1, preparing N target ions in a multi-dimensional ion chain into a unified initial quantum state in an imprisoning system of an ion trap; s2, the control module outputs N radio frequency signals with different frequencies and amplitudes, drives the acousto-optic modulation unit to output N diffracted light beams to N ions, and lasts for a fixed time; s3, the control module obtains the probability that each ion is excited to a set quantum state, and obtains the Rabian frequency of each ion according to the probability; and S4, the control module updates the output of the iteration control module by adopting a feedback control law mode according to the RH frequency of the ions obtained when the ions are measured, the target RH frequency of the ions and the amplitude of the radio frequency signal irradiated to the ions until the RH frequencies of the N target ions reach a preset condition. The invention provides a universal method for realizing any light intensity distribution in multi-ion addressing of an acousto-optic modulation unit.

The invention discloses an optical power compensation method, which comprises the following steps of: determining the Rabian frequency of trapping ions based on control light incident to the trapping ions; wherein the control light is output by the power adjusting module, is transmitted by the transmission optical fiber and is generated after being separated by the polarization light splitting module; performing power compensation on the control light according to the Labar frequency; and verifying the compensated control light based on gate control. By utilizing the method, the trapping ions are used as in-situ sensing probes to directly sense the effective action intensity (namely the pull ratio frequency) of the control light actually received by the trapping ions, and the compensation effect of the control light is verified through gate control verification, so that an indirect feedback mode depending on an external light splitter and a photoelectric detector is abandoned; the stability of light control and the accuracy of quantum gate operation in long-time quantum calculation are remarkably improved, meanwhile, full-automatic operation is supported, and the efficiency and reliability of the system are greatly improved.

This invention discloses a highly efficient cascaded GHZ state preparation method and its application based on an adiabatic fast channel, comprising: arranging atoms in a laser field according to four scales of GHZ states; for the initial state with a single-atom arrangement, directly preparing the GHZ state; for the initial state with a 2k atom array arrangement, inserting a π space in the ground state space between two RAP pulses. g The pulse sequence structure is used, and a ground state space π is applied after the evolution is complete, consisting of non-adjacent bits. g The laser pulse enables the preparation of cascaded GHZ states. By optimizing the Rabi frequency of the RAP pulse and the frequency difference between the laser and the atomic transition energy level, the spatial modulation characteristics of the Rydberg interaction are combined with the robustness of adiabatic manipulation. This unifies the preparation process of GHZ states of different scales, significantly reduces the operational complexity, and thus achieves high-fidelity and robust preparation of multi-scale cascaded GHZ states.

The present disclosure relates to quantum computing related methods, systems, and devices for determining a phase modulation function (Φ(t)) for a laser pulse implementing an arbitrary quantum gate for a qubit implemented by a trapped particle, comprising obtaining a Rabi frequency (Ω), and a trap frequency (ω) for the laser pulse and the trapped particle, determining, based on the Rabi frequency (Ω) and the trap frequency (ω), the phase modulation function (Φ(t)) for the laser pulse such as to minimize an effect of a photon recoil of the trapped particle induced by said laser pulse on a gate fidelity of the quantum gate, as well as to a corresponding method for performing an arbitrary quantum gate as well as to a system for modulating laser pulses used to implement one or more quantum gates for a subset of qubits in a quantum register, and to a quantum computer.

The invention discloses a vector magnetic field self-calibration measurement system and method based on microwave-driven Rabian oscillation, and the method comprises the steps: carrying out the optical polarization of atoms, and applying a plurality of static magnetic fields in known directions as a reference; three microwave polarization ellipse (MPE) modes are excited to drive atoms to generate Lab oscillation, and Lab frequencies of different hyperfine transitions are measured through detection laser; a microwave field vector parameter is solved through multi-direction data fitting, and system self-calibration is achieved; and measuring the Rabian frequency in the magnetic field to be measured under the calibrated microwave field, and performing inversion to obtain complete vector information of the magnetic field. According to the invention, atoms are used as a built-in reference and a sensor at the same time, an external standard magnetic field or mechanical rotation is not needed, high-precision, full-automatic and self-calibration vector magnetic field measurement is realized, and the device has the advantages of simple structure, strong anti-drift capability, high measurement precision and the like.

A quantum processing unit comprising: first qubits and second qubits arranged alternatingly, wherein each two adjacent qubits are subject to a first two-qubit interaction, wherein each qubit is adjacent to at least two qubits; a first source configured to drive the first qubits with a first Rabi frequency; a second source configured to drive the second qubits with a second Rabi frequency; and a set of mediator qubits.